How To Prevent Poor Acoustics in Open Offices

Whether touted for its collaborative benefits or cost savings, open-office design is here to stay. So are its challenges, especially acoustics. That’s all the more true in offices that have moved to benching, with employees sitting just a few feet away from each other, at long desks on which computer workstations are set up. Meanwhile, companies continue to eliminate partitions, carpets, and even sometimes acoustical ceilings, while adding wood, glass, and other sound-reflective surfaces, making office acoustics an even bigger issue.

When there are no strong acoustical design elements in such offices, they end up with “high noise levels, high reverberations, lower productivity, stress, and [people with] an inability to focus or do what needs to be done without bothering other people,” says Niklas Moeller, vice president, K.R. Moeller Associates Ltd. “We are starting to see a little bit of push back against this negative outcome. People predominantly spend their day trying to do individual focus work, and if you design a workplace with the intention of supporting that, collaboration also improves.” He points to Gensler’s 2013 Workplace Survey, in which 53 percent of employees reported they were disturbed by others when trying to focus. In the Oxford Economic Survey of 2016, employees identified sound issues as their number-one problem, he notes.

Sean Browne, principal scientist, Armstrong World Industries, notes that post-occupancy surveys of indoor environmental quality done by the Center for the Built Environment at the University of California, Berkeley, have found that satisfaction has increased over time in the areas of layout, lighting, and comfort, while satisfaction with acoustics remains low. “That metric has not moved in the past decade,” he says. Noise continues to be a problem, and more people are using headphones at the jobsite, Browne says.

The benefits of good acoustics include increased worker productivity and job satisfaction. “There is a strong push to consider the wellness of the space and create environments that are good for occupants,” Moeller says. “Poor acoustics lead to increased absenteeism and ‘presenteeism,’ meaning [employees] are there but are distracted.” In addition to lost productivity, the consequences of noise distraction include the loss of privacy and confidentiality, he says.

Ceilings and sound masking

When it comes to ceiling design in open spaces, there is more use of “baffles” and “blades,” which are sound-absorbing elements that hang from the ceiling, Browne says. “We have clouds, hung suspended like a mini ceiling, not just wall-to-wall rectangular drop ceiling tiles.” Also including wall treatments, these materials are continually updated and can look like wood or metal, have perforations, and are available in different colors and fabrics. “Ninety percent are for acoustical purposes. We want to absorb sound to reduce echo and reverberation time,” he says, to block and absorb intelligible sound, and keep speech privacy high.

As distractions increase and speech privacy declines, facility managers are taking a hard look at their options. “People are concerned, and facility managers are looking at tools that are available, and sound masking is a lower cost option,” says David Sholkovitz, vice president of marketing at Cam bridge Sound Management. “You don’t have to make physical changes to the floor plan or sacrifice design.”

The move to more open offices has spurred greater use of sound masking technology, says David Smith, vice president of marketing at Lencore Acoustics Corp.

Sound masking is designed to create comfortable sound that can be tuned or changed according to the internal environment. “Sound masking is not about blocking sound, but about making low-level sound unintelligible,” says Daniel Perruzzi, Jr., principal and senior partner at Margulies Perruzzi Architects.

Facility managers have become more educated and are looking at sound masking earlier when designing new spaces. “Most space planners have a network of people they talk to that includes sound masking experts,” says Smith. Of course, sound masking installed during construction is much cheaper than retrofitting a space after the fact, when a design was not well thought out.

“Products have gotten better and are easier to install,” Sholkovitz notes. Improvements in sound-masking technology include improved energy efficiency; networked solutions, where each individual speaker can be controlled and accessed from a computer or a server closet; and better combinations of music, paging, and sound masking, Sholkovitz explains.

In addition to cost, another good reason to install masking at the beginning of a project, before people move in, is so they don’t notice it but rather acclimate quickly to the sound. If sound masking must be added after the fact, people may initially be annoyed by it. “People don’t want additional sound in their space when they know about it,” says Albert Maniscalco, a partner with Cerami & Associates. Ramping up the system over a period of time also makes it easier for workers to adjust.

Perruzzi encourages facility managers to consider sophisticated sound-masking systems that can vary sound output, either above the ceiling or mounted in the ceiling, with the ability to tune individual speakers. With customization comes control, making it possible to “pump more sound masking” into noisy areas.